When (way back in 1978) I did my honours year in Melbourne about a
comparison of social behaviour of the House & Tree Sparrows (based on the
aspect of sexual dimorphism or not), I collected and weighed and measured
many of them and whilst I can't find the data right now (and sadly I never
published any of it - if only I had known of a future HANZAB), I do recall
that the range of weights of House Sparrows seemed to me to be very wide, as
in a high standard deviation relative to the mean. So presumably there is a
lot for selective pressures to work on. Not that I know of any outcomes.
Philip
-----Original Message-----
From: Birding-Aus On Behalf Of
Jim Tate
Sent: Monday, 16 June 2014 6:24 AM
To: Patrick Scully;
Subject: Spanish Sparrow
Bringing the (Spanish) Sparrow discussion back to Australia for the
moment....
On three trips to the Brisbane area in the last ten years I was surprised by
the low numbers and small size of the Passer sp. around town. Here in
Washington, DC they are large, dirty, and everywhere. Perhaps Brisbane is
just cleaner than DC so there is less to eat. I know that in Brisbane they
can't sit around smoking butts off the ground like they can in DC. Or maybe
it is something else that keeps their numbers and size down. I am reminded
that in England the P. domesticus appear to be dropping in numbers and
distribution. Conventional wisdom blames the decline in horses, also
essentially absent in DC.
I am reminded of a story I once read of an ornithologist that took a trip
across Europe and Asia by horse cart. Somewhere in the steppes of Russia he
stopped and shot all of the House Sparrows following his horse cart to
prevent a range extension. Probably apocryphal. -TATE
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